The present invention relates to a cassette for spare lengths of light waveguides to be used at a site where waveguides are to be spliced which has a fixed part supporting the outer walls and a rotatable part with a core arranged therein.
A number of devices for storing spare lengths of light waveguides to be used at the splicing site are known already. Thus, for example, in DE-PS 27 21 300 a cassette provided with an annular take up region used for winding up spare lengths of light waveguides is described with which it is possible, if several turns of the respective optical fiber are loosely inserted, to pull this fiber out when needed, tightening the turns at the inner edge of the particular ring element; to splice the end of the optical fiber; to measure and test the piece of cable, and, after these operations, to reinsert the optical fiber into the cassette, without danger of damage.
In another known device (DE-OS 31 36 738), used for the separation and connection of individual light waveguides, a cable element at the entrance and/or exit of the device is provided. The waveguides are guided singly or in pairs between the comb teeth of this element. This arrangement prevents the waveguides from accidentally coming out of the comb teeth when installed. Between the comb elements are sorting compartments in which spare lengths of light waveguides can be stored.
Another known device (DE-OS 34 28 856) consists of a flat parallelepiped housing with an opening that can be closed by a cover in which the individual light waveguides can be inserted.
In a device disclosed in DE-OS 35 32 314, which incorporates an extremely flat design, a non-jamming withdrawal and reinsertion of one end of a waveguide is permitted. In order to accomplish this, a cylindrical magazine is provided with helical spirals in the flat cylindrical chamber, so that it is readily possible to withdraw and insert the waveguide in radially external spirals.
The known device in DE-OS 35 32 313 should also be mentioned, in which a magazine for this purpose consists of a fixed outer part that carries the outer edge wall and a winding part rotatable therein.
In all of the prior art cited, the devices are only suitable to store a single light waveguide or a light waveguide ribbon. A light waveguide ribbon is made up of several light waveguides joined together to form a flat cable.
In view of the limitations of the prior art devices, there is a need to improve such magazines by making them more suitable for handling in an installation on the site than the known magazines. Above all, the improved magazine should be able to store several light waveguides.